After being told by Fairfax County that "a fair share is no share," the District of Columbia and suburban Maryland yesterday decided to go to court to force Fairfax to accept some of the smelly and messy sludge that the Blue Plains regional sewage treatment plant produces everyday.

At a showdown convened at the Metropolitan Washington Council of Government, Montgomery County Executive James P. Gleasonopened the seasion by saying:

"The gut issue is that Fairfax County doesn't want to take anymore sludge."

"I object to that characterization," said Fairfax Board of Supervisors Chairman John F. Herrity from the other end of the table. "We have never agreed to take any undigested sludge."

Whereupon Jean Levesque, administrator for water resources in the District, read from the 1974 Blue Plains agreement:

". . . the parties agree . . . to accept sludge, whether digested, undigested or both, on a fair-share basis . . ." The document, itself the result of a court decision ordering the users of Blue Plains to solve their problem, was signed for Fairfax by then Board Chairman Jean Packard.

Herrity insisted, though: "We have never agreed to take undigested sludge."

But Gleason countered: "I don't know how you can interpret this agreement in any other way."

Blue Plains produces 475 tons of raw sludge daily. When more advances waste treatment begins in 1980, the daily production of sludge will amount to 1,500 to 1,800 tons.

Only about 40 tons can now be converted to compost at the experimental recycling center at Beltsville. The rest has to be buried in 30-incdeep trenches, all of them in Montgomery and Prince George's counties. A new trenching operation is scheduled to begin at Oxon Cove in the Southwest the District next July, but it will be able to handle only 600 tons daily and only for five years.

Because trenching is expensive - $40 for each ton of sludge - and consumes valuable land - 1,000 tons, or two days' production, require 1 acre - suburban Maryland wants Fairfax to take a share.

Fairfax's share, if based on its use of Blue Plains, would be about 41 tons daily.

Herrity, a minority of one at the COG meeting, argued that Fairfax was already taking more than its share of regional solid waste in the form of the District's garbage and trasgat the landfill near Lorton. As for local government not honoring agreements, he said, "we haven't seen a dime from the District of Columbia for the $9.5 million recycling center that was supposed to be built at the Lorton landfill."

One high suburban Maryland official, who declined to be identified, said the landfill was a "phony issue." The land, he said, was orignially owned by the District. By giving the land to Fairfax, the official said, the District not only helped solve its own solid-state problem but Fairfax's too, since the county was running out of room at its smaller landfill on I-66.

The Fairfax superviors have twice sludge, and Herrity told his regional colleagues yesterday: "I know of no indication its position is going to change . . . I'm not prepared to make any recommendation (to accept a share)"

Some Fairfax officials are fearful that if the county starts accepting raw sludge, it might end up getting more than a proportional share absed on it use of Blue Plains.

The dispute involving Fairfax is holding up a permanent solution to disposal of sludge, which is a partly soldi by product of the settling process in sewage treatment. The parties must sign an agreement on a permanent plan by Dec. 31.

"The agreement expires on Dec. 31," one local official said, "but there will be sludge Jan. 1."